
AMERICAN MEGATRENDS, INC.

Omni Business Partner

Processor     80486SX/80487SX/80486DX/ODP486SX/80486DX2/Pentium Overdrive
Processor     20/25/33/50(internal)/66(internal)MHz
Speed
Chip Set      AMI
Max. Onboard  20MB
DRAM
Cache         256KB
BIOS          AMI
Dimensions    330mm x 218mm
I/O Options   Floppy drive interface, IDE interface, parallel port, PS/2
              mouse port, serial ports (2), VGA port
NPU Options   None

[Image]

                                CONNECTIONS

  Purpose                  Location     Purpose                 Location

  IDE interface               J2        RJ48 10BaseT               J35
                                        connector

  Onboard battery             J5        SCSI LED                   J37

  PS/2 mouse connector        J6        Speaker                    J38

  External battery            J8        Reset switch               J39

  Serial port 2               J11       Turbo switch               J40

  Secondary cache             J12       BNC 10Base2 connector      J41
  connector

  SCSI connector              J15       IDE interface LED          J42
  (internal)

  Serial port 1               J16       Turbo LED                  J43

  SCSI 1                      J17       Keyboard lock              J44
                                        connector

  VGA port                    J31       Parallel port              P3

  AUI connector               J32       Floppy drive               P4
                                        interface

                        USER CONFIGURABLE SETTINGS

              Function                 Jumper/Switch         Position

     PowerGood signal from DS1231           J1                Open

      PowerGood signal not from              J1               Closed
      DS1231 (not installed)

     Factory configured do not              J3                 N/A
      alter

     Flash ROM programming                  J7                Open
      disabled

      Flash ROM programming                  J7               Closed
      enabled

     Factory configured do not             J20               Closed
      alter

     Video memory DRAM cycle               J21                Open
      select (6 MCLK RAS)

      Video memory DRAM cycle               J21               Closed
      select (7 MCLK RAS)

     VGA controller IRQ NOT                J22                Open
      routed to IRQ9

      VGA controller IRQ routed to          J22               Closed
      IRQ9

     Enables IRQ12 for onboard             J27              pins 2 & 3
      PS/2 mouse                                              closed

      Disables IRQ12 for onboard            J27              pins 1 & 2
      PS/2 mouse                                              closed

     Enables IRQ10 for NCR SCSI            J28               Closed
      I/O processor

      Disables IRQ10 for NCR SCSI           J28                Open
      I/O processor

     Enables IRQ11 for onboard             J29               Closed
      LAN controller

      Disables IRQ11 for onboard            J29                Open
      LAN controller

     VGA onboard controller                J33               Closed
      enabled

      VGA onboard controller                J33                Open
      disabled

     CMOS memory normal operation          J34              pins 2 & 3
                                                              closed

      CMOS memory clear                     J34              pins 1 & 2
                                                              closed

     Onboard SCSI termination              J36              pins 2 & 3
      chip enabled                                            closed

      Onboard SCSI termination              J36              pins 1 & 2
      chip disabled                                           closed

     Factory configured do not            SW1/1                Off
      alter

     Monitor type select                  SW1/2                Off
      monochrome

      Monitor type select color            SW1/2                On

      64KB Cache enabled               SW2/1, 2, 3, 4           Off

      256KB Cache enabled              SW2/1, 2, 3, 4           On

                       SERIAL PORT IRQ CONFIGURATION

    Port 1 (J16)       Port 2 (J11)           J25               J26

         IRQ4             IRQ3            pins 1 & 2        pins 1 & 2
                                            closed            closed

          IRQ3             IRQ4            pins 2 & 3        pins 2 & 3
                                            closed            closed

                        CPU FREQUENCY CONFIGURATION

         Frequency                     J9                     J10

            33 Mhz                   Open                   Open

             25 MHz                  Closed                  Open

                    CPU TYPE CONFIGURATION

      CPU Type                J13                 J14

       80486SX         pins 1 & 2 closed   pins 2 & 3 closed

       80487SX         pins 2 & 3 closed       all closed

       80486DX         pins 1 & 2 closed       all closed

      ODP486SX         pins 2 & 3 closed       all closed

      80486DX2         pins 1 & 2 closed       all closed

  Pentium Overdrive    pins 2 & 3 closed       all closed

  MEMORY CLOCK SPEED OF THE CLGD5426

  Frequency      J23          J24

  50.11 MHz     Closed       Closed

  44.74 MHz     Closed        Open

  41.16 MHz      Open        Closed

  37.58 MHz      Open         Open

                            DRAM CONFIGURATION

     Size         Bank 0          Bank 1        Bank 2         Bank 3

     1MB         (1) 256K x        NONE          NONE           NONE
                    36

     2MB         (1) 256K x     (1) 256K x       NONE           NONE
                    36              36

     4MB        (1) 1M x 36        NONE          NONE           NONE

     6MB         (1) 256K x     (1) 256K x    (1) 1M x 36       NONE
                    36              36

     8MB        (1) 1M x 36    (1) 1M x 36       NONE           NONE

     10MB        (1) 256K x     (1) 256K x    (1) 1M x 36   (1) 256K x 36
                    36              36

     12MB       (1) 1M x 36    (1) 1M x 36    (1) 1M x 36       NONE

     16MB       (1) 1M x 36    (1) 1M x 36    (1) 1M x 36    (1) 1M x 36

     16MB       (1) 4M x 36        NONE          NONE           NONE

     20MB       (1) 1M x 36    (1) 4M x 36       NONE           NONE

     24MB       (1) 1M x 36    (1) 1M x 36    (1) 4M x 36       NONE

     32MB       (1) 4M x 36    (1) 4M x 36       NONE           NONE

     36MB       (1) 1M x 36    (1) 4M x 36    (1) 4M x 36       NONE

     40MB       (1) 1M x 36    (1) 1M x 36    (1) 4M x 36    (1) 4M x 36

     48MB       (1) 4M x 36    (1) 4M x 36    (1) 4M x 36       NONE

     64MB       (1) 4M x 36    (1) 4M x 36    (1) 4M x 36    (1) 4M x 36

